search for: psigamma

Hello, I am trying to find a hessian matrix that involves log(gamma(1/p)) second derivative, p being one of the parameters of the function. I am using a function "deriv" with the hessian=TRUE option, but psigamma is not on the list of derivative functions. I know that it is possible to use 'psigamma(p,deriv)', but it doesn't work with 1/p. Does anybody can help with this? Thanks, Ana Maria

Hello, I was wondering if the functions deriv3(), deriv() etc. could be extended to handle psigamma() and its special cases (digamma(), trigamma() etc.). From the error message it seems that 'psigamma' needs to be added to the derivatives table. This might be easy since psigamma() has a deriv argument. Additionally, this error message is also obtained when requesting for the Hessian of t...

...by prod or sum etc), without having to write and append to a file? Question 2: > deriv(~gamma(x),"x") expression({ .expr1 <- gamma(x) .value <- .expr1 .grad <- array(0, c(length(.value), 1), list(NULL, c("x"))) .grad[, "x"] <- .expr1 * psigamma(x) attr(.value, "gradient") <- .grad .value }) BUT > deriv3(~gamma(x),"x") Error in deriv3.formula(~gamma(x), "x") : Function 'psigamma' is not in the derivatives table What I want is the expression for the second derivative (which I believe is...

Hi R-users,   I wrote a code to evaluate double sum as follows:   ff2 <- function(bb,eta,z,k) { r <- length(z) for (i in 1:r) { sm1 <- sum((z[i]*bb/2)*(psigamma((0:k)+eta+1,deriv=0)/(factorial(0:k)*gamma((0:k)+eta+1))))  sm2 <- sum((besselI(z[i]*bb,eta)*log(z[i]*bb/2) - sm1)/besselI(z[i]*bb,eta))  sm2 } ff2(bb,eta,z,10)     but it gave me the following message:   > source(.trPaths[5], echo=TRUE, max.deparse.length=10000) Error in source(.trPaths[5],...

Hi R-users, Does R has a topic on newton's method? Thank you for the info.

Hi, Is there any R library that is capable of handling polygamma function (Hurwitz zeta function also works)? I am aware of digamma(0 and trigamma(), but could not find more advanced versions. I'd appreciate any help. Hakan Demirtas

...than slanted. o ppr() now fully supports categorical explanatory variables, ppr() is now interruptible at suitable places in the underlying FORTRAN code. o princomp() now warns if both `x' and `covmat' are supplied, and returns scores only if the centring used is known. o psigamma(x, deriv=0), a new function generalizes, digamma() etc. All these (psigamma, digamma, trigamma,...) now also work for x < 0. o pchisq(*, ncp > 0) and hence qchisq() now work with much higher values of ncp; it has become much more accurate in the left tail. o read.table() now allo...

...than slanted. o ppr() now fully supports categorical explanatory variables, ppr() is now interruptible at suitable places in the underlying FORTRAN code. o princomp() now warns if both `x' and `covmat' are supplied, and returns scores only if the centring used is known. o psigamma(x, deriv=0), a new function generalizes, digamma() etc. All these (psigamma, digamma, trigamma,...) now also work for x < 0. o pchisq(*, ncp > 0) and hence qchisq() now work with much higher values of ncp; it has become much more accurate in the left tail. o read.table() now allo...

...6.79d and later. DEPRECATED & DEFUNCT o The 'extended' argument is deprecated in strsplit(), grep(), grepl(), sub(), gsub(), regexpr() and gregexpr() (not just the value extended = FALSE) and will be removed in R 2.11.0. BUG FIXES o trigamma(x) and other psigamma(x, n) calls are now accurate for very large abs(x). (PR#14020) o [g]sub(perl=FALSE, fixed=FALSE) could use excessive stack space when used with a very long vector containing some non-ASCII strings. o The default method of weighted.mean(na.rm = TRUE) did not omi...

...6.79d and later. DEPRECATED & DEFUNCT o The 'extended' argument is deprecated in strsplit(), grep(), grepl(), sub(), gsub(), regexpr() and gregexpr() (not just the value extended = FALSE) and will be removed in R 2.11.0. BUG FIXES o trigamma(x) and other psigamma(x, n) calls are now accurate for very large abs(x). (PR#14020) o [g]sub(perl=FALSE, fixed=FALSE) could use excessive stack space when used with a very long vector containing some non-ASCII strings. o The default method of weighted.mean(na.rm = TRUE) did not omi...

...ents are of compatible dimensions. o qbinom() now is accurate also in (large size, small prob) cases. (PR#13711) o The calculation of the Spearman p-value in cor.test() is slightly more accurate in some cases. (PR#13574) o The digamma(), trigamma() and psigamma() functions could be inaccurate for values of x around 1e-15 due to cancellation. (PR#13714). o median.default() was altered in 2.8.1 to use sum() rather than mean(), although it was still documented to use mean(). This caused problems for POSIXt objects, for...

...ents are of compatible dimensions. o qbinom() now is accurate also in (large size, small prob) cases. (PR#13711) o The calculation of the Spearman p-value in cor.test() is slightly more accurate in some cases. (PR#13574) o The digamma(), trigamma() and psigamma() functions could be inaccurate for values of x around 1e-15 due to cancellation. (PR#13714). o median.default() was altered in 2.8.1 to use sum() rather than mean(), although it was still documented to use mean(). This caused problems for POSIXt objects, for...

...errors in NEWS file formatting. o deparse() gains a new argument 'nlines' to limit the number of lines of output, and this is used internally to make several functions more efficient. o deriv() now knows the derivatives of digamma(x), trigamma(x) and psigamma(x, deriv) (wrt to x). o dir.create() has a new argument 'mode', used on Unix-alikes (only) to set the permissions on the created directory. o Where an array is dropped to a length-one vector by drop() or [, drop = TRUE], the result now has names if exactly one...

...errors in NEWS file formatting. o deparse() gains a new argument 'nlines' to limit the number of lines of output, and this is used internally to make several functions more efficient. o deriv() now knows the derivatives of digamma(x), trigamma(x) and psigamma(x, deriv) (wrt to x). o dir.create() has a new argument 'mode', used on Unix-alikes (only) to set the permissions on the created directory. o Where an array is dropped to a length-one vector by drop() or [, drop = TRUE], the result now has names if exactly one...